Skip to Main Content
High-color-depth LCD drivers require nF-range capacitors as the charge reservoirs to handle the glitch energy during the conversion of the DAC . The reference buffers based on multi-stage amplifiers can enhance the precision under low-voltage supplies, but are exposed to instability when loaded by such large capacitive loads (CL). Frequency compensation via damping-factor control  is capable of extending the CL-drivability up to 1nF, however, at the cost of penalizing the power (426μW) and area (0.14mm2). Although recent works [3-4] have enhanced gain-bandwidth product (GBW) and slew rate (SR) showing better FOMS (=GBW·CL/Power) and FOML (=SR·CL/Power), the CL-drivability has not been improved (i.e., 0.8nF in  and 0.15nF in ). This paper describes a three-stage amplifier managed to afford particularly large and wide range of CL (1 to 15nF) with optimized power (144μW) and die size (0.016mm2), being very suitable for compact LCD drivers  with different resolution targets. The design barriers are methodically surmounted via local feedback loop (LFL) analysis expanded from , which is an insightful control-centric method. Measured at 15nF CL, the attained FOMS (FOML) is >;4.48× (>;2.55×) beyond that of the state-of-the-art (Fig. 21.6.1).